Communications cables, such as shielded and unshielded twisted pair cables, coaxial cables, and fiber optic cables, transmit data, voice, video and/or audio information in the telecommunications industry. Network equipment enclosure rack systems are well-known in this industry for managing and organizing such cables as they are routed to and from various destinations.
Rack systems typically include a distribution frame rack or cabinet on which one or more patch panels, network equipment, fiber optic enclosures such as fiber optic trays, and the like are mounted. Rack systems serve various functions, including their use as slack trays, splice trays, cable organizers and patch panels. These rack systems also serve as interconnect or cross-connect enclosures when they interface with equipment. Additionally, rack systems may serve as a telecommunications closet, allowing the cables to be terminated, spliced, patched and/or stored at various places along their length.
The rack is usually formed from a frame having mounting apertures located along the vertical legs or walls of the rack. Patching equipment, such as a patch panel, is mounted onto the rack so as to generally define a patching side, where patch cords from another active device or another patch panel can be cross-connected and interconnected, and a distribution side, where cables from network equipment and/or work station areas are terminated.
Generally, some structures or features for cable management for rack-mounted fiber optic trays are provided on both sides of the rack to support and route the cables. With the increasing use of fiber optic connectors as applied to connector rack systems, proper cable management and bend radius control has become increasingly important.
User requirements for optical fiber patch cord management vary greatly. Some users may prefer a full width trough for maximum protection of the patch cords, and some may prefer a minimal trough or J-hook for easier access to the cords and connectors/adapters. Typically these patch cord management structures are integral with the tray. In some instances, a user may install a tray into a server cabinet, then learn that equipment rail placement is not adequate to allow use of a trough, in which case the tray is removed altogether.
Also, typically communications cables entering a shelf or enclosure enter in a direction normal to the side or rear of the shelf (often through a gland or similar structure for securing the cable). Cables entering the shelf may be rather stiff, and in the case of fiber optic cables may have a minimum acceptable bend radius that reduces the degree to which the cables are permitted to flex. As such, a path of entry that is normal to the side or rear can create large cable loops which are difficult to manage and/or which may require undue amounts of space adjacent the shelf.